Slack-adjuster for brakes.



PATEN'IED APR. 2; 190. 7. J. M. HINBS. I SLACK, ADJUSTER FOR BRAKES.

APPLICATION FILED AUG. 2, 1906.

3 SHEETS-SHEET 1.

No. 848,993. PATENTED APR. 2, 1907. J. M. amps. SLACK ADJUSTER FORBRAKES.

APPLICATION FILED AUG. z, 1906.

s swims-31mm z Witneaoh l h z" 2 rnE NORRIS PErsRs co, wAsHmcwN. u. c.

No. 848,993. PATENTED APR. 2, 19 07. .J. M. HINES.

SLACK ADJUSTER FOR BRAKES.

APPLICATION FILED AUG. 2, 1906.

3 SHEETS-SHBET 3.

JAMES MICHAEL HINES, OF ALBANY, NEW YORK.

SLACK-ADJUSTER FOR BRAKES.

Specification of Letters Patent.

Patented April 2, 1907.

Application filed August 2, 1906. Serial No. 328,845.

To all whom it may concern:

Be it knownthat I, J AMES MIOHAEL HINEs, residing and having apost-office address at No. 3 Martin avenue, city of Albany, State of NewYork, have invented certain new and useful Improvements inSlack-Adjusters for Brakes; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

My invention relates to slack-adjusters for car-brakes, and is intendedto supply improved means for taking up the slack due to the wear of thebrake-shoes and wheels and the stretching and bending of thebrake-operating levers and rods.

In carrying out my invention I provide an independent retainer connectedto each brake beam by a lost motion device and adapted to be set by thebrake applying movement to limit the withdrawal of the brake-shoes onthe releasing movement to the range of movement of the lost-motiondevice. This limitation of the withdrawal of the brake-shoes wouldordinarily prevent the return of the live lever (and the piston of theair-brake cylinder when air-brakes are employed) to its originalposition. To avoid this, I provide mechanism to take up the slack in thesystem of brake-applying levers and rods on the releasing movement ofthe brakes and to thus allow the return of the live lever to its normalposition, the slack-take-up mechanism being provided with means forholding the slack taken up. I

My improvements will be understood from the following specification anddrawings,

which describe and illustrate a structure which embodies the preferredform of my invention as applied to a four-wheel truck.

In the drawings, Figure 1 is a plan view of a four-wheeled truck-equipped with brake mechanism embodying a preferred form of myimprovements. Fig. 2 is a side elevation on line 2 2 of Fig. 1. Fig. 3is a detail view of the retainer-ratchet mechanism. Fig. 4 is a detailview of the slack take up ratchet mechanism. Fig. 5 is a cross-sectionon line 5 5 of Fig. 4.

Referring to Figs. 1 and 2, A is the rod which extends to the piston ofthe brakecylinder (not shown) and which is connected to and actuates thelive lever B, pivoted in a strut C, extending from the brakebeam D tothe truss E. This live lever B extends downwardly and transversely, asillustrated, and has connected to its lower end the rod F, which isconnected to the lower end of the dead lever G. The dead lever G issupported in substantially the same manner as the live lever B. Thebrake-shoes a are secured to the brake-beam D and hung from the end barof the truck in any appropriate manner, and springs I) serve to draw thebrake-shoes away trom the wheels when the brakes are released.

The retaining mechanism and lost-motion connection is constructed in thefollowing manner: Projecting upwardly from the strut C is a short forkedarm 0, in the fork of which the connecting-rod d is pivoted. The otherend of the rod d is provided with a slot which plays on a pin in theforked lower end of the lever e, which lever is pivoted in a bracket f,secured to the cross-bar H. Pivoted to the upper end of the lever e is aconnecting-rod g, which is secured at its other end to the box h,sliding on the rack-bar i and carrying retaining-pawl is, adapted tointerlock with the teeth on the rack-bar i. The dead lever G is pivotedin the strut C, extending from the brake-beam D to the truss E Thisstrut O is provided with a forked arm 0, connected to the rod (1, thelever e, the connecting-rod g, and the ratchet-box h, all of these partsand supports being similar to corresponding parts at the other end ofthe truck. Pivoted to the upper end of the lever G is a connecting-rodm, which is attached to the box n, sliding on the rack-bar 0 andcarrying the pawl p, adapted to interlock with the teeth on therack-bar. The pawl 7c is provided with a pin 7, so that when it isdesired to release the slack which has been taken up for the applicationof new shoes, &c., the pawl 76 may be turned on its pivot out ofengagement with the rack-bar and retained in this inoperative positionby swinging the hook s over the pin 1". A similar arrangement isprovided for the box h. To the pawl p is fastened an arm 15, to whichthe rod u is connected, and this rod a has a bent portion at its otherend, adapted to be placed in the slot in the connecting-rod m, as shownin Fig. 1. The purpose of this rod 10 is to allow the attendant to turnthe pawl 19 on its pivot, thus disengaging it from the rack 0 andrendering it possible to move the box n to the right to release theslack which has been taken up when it is desired to apply new shoes, &c.

The operation of the parts is as follows: If

power is applied to the brake-cylinder, the

movement of the piston will pull 011 the rod A and move the brake-beamand brakes toward the wheels. If the length of the slot in theconnecting-rod d is less than the distance through which it is necessaryto move the brakes in order to bring them into contact with the wheels,the end of the slot in the rod d comes into contact with the pin on thelever e and turns that lever on its pivot, thus moving theconnecting-rod g and the box it to the left, the pawl is riding on therack i. At the same time a similar action has taken place in connectionwith the other brakebeam through the rod d, the lever e, the rod 9, andthe box h. When the brakes are released, the pawls in the boxes h and hengage with their respective racks, preventing the return of the leverse and e to their original positions, and thus limiting the movement ofthe brake-beams and shoes away from the wheels and retaining thatportion of the movement of the brake beams and shoes Which is due to theslack in the mechanism. On the return movement of the brake-piston thelive lever B moves with the strut C until the right-hand end of the slotin the connecting-rod d engages with the pin on the lever 6. Thismovement is sufficient to release the brakes. The further movement ofthe brakepiston in returning to its original position turns the livelever on its pivot and through the connecting-rod F turns the dead leverG and through the connecting-rod m causes the box n to slide to the leftover the rack 0. At the end of this movement the pawl 32 engages withthe rack 0 and prevents the return of the dead lever, thus taking up theslack in the brake mechanism and establishing a new fulcrum for thesystem of levers. Thereafter upon each release the brake-shoes fall backonly the distance allowed by the slots inthe rods d and d, and upon anyapplication of the brakes the movement is through only the distanceallowed by these slots until the wear of brake-shoes or wheels or thebending of the levers and rods has created sufiicient slack to permitthe movement of the box n another notch to establish a new fulcrum forthe system.

It will be understood that though I have described in detail thepreferred form of my invention in order that those skilled in the artmay be able to construct the same, yet my invention is not limited tothe specific details so described.

Having thus described my invention, what I claim is 1. In a brakemechanism for vehicles, brake-beams, brake-shoes carried thereby,brake-applying mechanism for moving said beams'and shoes toward thewheels to apply the brakes, a separate mechanism associated with eachbrake-beam and independent of the brake-applying mechanism for retainingthat portion of the brake-applying movement which is due to the slack inthe brake mechanism, and means for automatically adjusting thebrake-applying mechanism to take up the slack on the releasing movementof the brakes.

2. In a brake mechanism for vehicles, brake-beams, brake-shoes carriedthereby, means for moving said beams toward the wheels to apply thebrakes, a retainer attached. to each brake-beam actuated by thebrake-applying movement thereof to limit the movement of the brakebeamaway from the wheels, and means for automatically adjusting thebrake-applying mechanism to take up the slack therein on the releasingmovement of the brakes.

3. Ina brake mechanism for vehicles, a system of levers, brake-beamsadapted to be actuated by said levers, brake-shoes carried by saidbeams, a retainer connected to each brake-beam. by a lost-motion deviceand adapted to be set by the brake-applying movement to limit thewithdrawal of the brake-shoes, and means for takin up the slack in thesystem of levers on the rake-releasing movement.

4. In a brake mechanism, a lurality of brake-beams, brake-shoes carriethereby, a

live lever mounted on a single free pivot fixed with relation to one ofsaid brake-beams, a dead lever mounted on a pivot fixed with relation toanother of said brake-beams, means for creating a fulcrum for said deadlever fixed with relation to the vehicle or truckbody, means independentof said levers for limiting the movement of the brake-beams away fromthe wheels, and means for automatically adjusting the position of thefulcrum for the dead lever on the releasing movement of the brakes.

5. In a brake mechanism for vehicles, two brake-beams, brake-shoescarried thereby, a live lever mounted on a pivot fixed with relation toone brake-beam, a dead lever mounted on a pivot fixed with relation tothe other brake-beam, means for applying the braking power to one end ofthe live lever, a connection between the live lever and the dead lever,adjustable mechanism connected to each of the brake-beams and adapted tolimit the movement thereof away from the wheels, means for creating afulcrum for the dead lever fixed with relation to the truck-frame,

and means for adjusting the position of said.

fulcrum on the releasing movement of the brake mechanism.

6. In a brake mechanism for vehicles, two brake-beams, brake-shoessupported thereby, a live lever mounted on a pivot fixed with relationto one brake-beam and a dead lever mounted on a pivot fixed withrelation to the other brake-beam, means for applying the braking powerto the live lever, connections between the live lever and the"deadlever, a l vers, a

retaining-lever mounted adjacent to each brake-beam and connectedthereto by a lostmotion device, a rack adjacent to each of saidretaining-levers, pawls adapted to engage with the said racks,connections between the retaining-levers and said pawls, a rack mountedadjacent to the dead lever and a pawl connected to the dead leveradapted to engage with the said rack; substantially as and for thepurpose described.

7. In a braking mechanism for vehicles, a plurality of brake-beams,brake-shoes supported thereby, brake-applying levers mounted on pivotsfixed with relation to said beams, means for applying the braking powerto one of said levers, connections between said lepivotedretaining-lever mounted adjacent to each brake-beam and connectedthereto by a lost-motion device, a rack adj acent to each of saidretaining-levers, pawlboXes mounted on said racks, connections be-'tween the pawl-boxes and the retaining-levers, a rack adjacent to one ofthe brake-applying levers, a pawl-b OX sliding on said rack, andconnections between the said pawl-box and adjacent lever, substantiallyas described.

In testimony whereof I afiix my signature in presence of two witnesses.

JAMES MICHAEL HINES.

Witnesses:

A. L. KENDALL, A. D. FINKLE.

